Apparatus for assembly of interlocking containers



Jan. 3,- 1956 E. N. BURNETT 2,

APPARATUS F OR ASSEMBLY OF INTERLOCKING CONTAINERS Original Filed Oct. 5, 1950 3 Sheets-Sheet 1 saw my ear I N V EN TOR.

4- sow/mo w. BURNETT BY 22 WTW AT TOR/VE'YS Jan. 3, 1956 E. N. BURNETT 2,729,041

APPARATUS FOR ASSEMBLY OF INTERLOCKING CONTAINERS Original Filed Oct. 3, 1950 3 Sheets-Sheet 2 ATTORNEYS Jan. 3, 1956 E. N. BURNETT 2,729,041

APPARATUS FOR ASSEMBLY OF INTERLOCKING CONTAINERS Original Filed Oct. 5, 1950 S Sheets-Sheet 3 IN V EN TOR.

EDWARD IV. BURNETT BY ATTORNEYS United States Patent APPARATUS FOR ASSEMBLY OF INTERLOCKING CONTAINERS Edward N. Burnett, San Lorenzo, Calif., assignor to Gerber Products Company, Fremont, Micln, a corporation of Michigan Original application October 3, 1950, Serial No. 188,254, now Patent No. 2,651,153, dated September 8, 1953. Divided and this application March 16, 1953, Serial No. 342,630

7 Claims. (Cl. 53-44) This invention relates to new and useful improvements in methods and apparatus for assembly of interlocking containers. More particularly, the invention relates to new and useful methods and machinery for assembling and gluing pairs of interlocking container .units, such as those disclosed in my copending patent application for Container Construction, Serial No. 141,150, filed January 26, 1950, now Patent No. 2,651,449. This application is a division of my application Serial No. 188,254, filed October 3, 1950, now Patent No. 2,651,153. Reference is also made to my application Serial No. 342,629, filed simultaneously herewith.

Said copending application 141,150 discloses novel container constructions in which two or more units are adapted to be interlocked together, one of the outer cover flaps of each unit having an integral projecting tongue and the other outer cover flap of each unit having a corresponding recess receiving the tongue of the opposed unit. The top and bottom construction of the units are identical. Glue is applied to the undersurface of each tongue which adheres to the top surface of inner flaps which are exposed by reason of the recess cut in the outer flap which receives the tongue of the opposed box unit. The details of such box units are more completely described hereinafter in the body of the specification of this application.

The instant invention has for its principal object the assembly and gluing of pairs of such container units. It will be assumed that the blank for each box unit has been folded at successive 90 angles along score lines therein provided as set forth in my said copending applications and that the meeting edges of the side panels have been joined by means of a strip of adhesive tape or other suitable attaching means to hold the adjacent panels together. The operator of the machine disclosed in application Serial No. 188, 254, then forms a temporary bottom for each unit by folding down all of the flaps thereof, but no glue is applied at this stage of the assembly of the unit. Each unit is then filled with containers by means of a packing machine of substantially standard construction. The machine then performs the following steps:

(A) Each filled unit is packed, deposited on a conveyor belt and transported into the machine.

(B) Corresponding pairs are grouped together, the machine being so constructed that two units are positioned with their opposed sides abutting and are so conveyed that the two units proceed through the machine in such position. The timing of this station of the machine is such as to insure that units are paired together, and, if they are not so paired, further progress through the machine is halted until adjustment is made. After release from this station, the units are advanced through subsequent stages by a pusher bar bearing against the rear of the rearmost unit, release from the grouping station being timed to movement of said bar.

(C) The inner top flaps of each unit are forced downwardly so that they are horizontal and overlie the contents of the container.

(D) The outer top and bottom flaps are folded outward so that they assume a horizontal position projecting away from the container.

(E) Glue is applied to the undersurfaces of the outer top and bottom flaps.

(F) The outer top and bottom flaps are folded inwardly so that they are horizontal and overlie the container.

(G) The container is subjected to compression so that the glue causes the outer flaps of both the top and the bottom of each unit to adhere to the inner flaps thereof, the projecting tongues of one unit adhering to the portions of the inner flaps of the opposite unit exposed by the cutting away of recesses in the outer flaps.

(H) Further compression is applied until the glue has set sufiiciently for handling.

Further objects of the present invention will become apparent upon referring to the accompanying specification and drawings in which similar characters of reference represent corresponding parts in the several figures of the drawings.

Fig. 1 is an exploded perspective view of two container units prior to being assembled together;

Fig. 2 is a perspective view of a pair of units as finally assembled;

Fig. 3 is a side elevation of the unit assembly station and adjacent mechanism;

Fig. 4 is a top plan of the structure shown in Fig. 3.

Fig. 5 is a vertical section taken substantially along the line 5-5 of Fig. 3;

Fig. 6 is a fragmentary view of a portion of the unit assembly station showing the location of switches actuating the mechanism releasing pairs of units from this station;

Fig. 7 is a wiring diagram of certain electrical circuits employed in the unit assembly station;

Referring now to Figs. 1 and 2 there is illustrated a container construction such as that disclosed and set forth in my aforementioned patent application, Serial No. 141,150, filed January 28, 1950. It will be seen that the construction comprises two interlocking box units indicated generally by reference numerals X and Y, formed of corrugated paper or other suitable material. Fig. l is an exploded view of the two units prior to being assembled together. In Fig. 2 the two units are shown in interlocked position. The sides of each box unit form a rectangle in cross-section, the respective sides of which are indicated by reference numerals 21, 22, 23, and 24. The meeting edges of panels 22 and 23 are held together by a strip of gummed tape 25. The inner flaps of the top of each unit, which constitute extensions of side members 22 and 24, respectively, are designated by reference numerals 27 and 2S. Said inner flaps are folded on horizontal score lines disposed transverse to the direction of movement of the units through the machine. Said flaps meet along the center of the box unit when folded horizontal in completed form. The outer flaps of the tops of each of the units are designated by reference numerals 29 and 30 and constitute, respectively, extensions of side members 21 and 23. Said outer flaps are folded on horizontal score lines disposed parallel to the direction of movement of the units through the machine. Outer top flap member 29 has a projecting tongue 31 which projects out beyond the outline of side 24. Outer top flap member 30 has a corresponding recess 32 cut therein which is dimensioned and positioned to receive the projecting tongue 31 of the opposite box unit. By reason of the cutting away of the recess 32 in outer flap 30, a portion of inner flap 28 is exposed prior to assembly of the two units together, and when glue is applied to the underside of the projecting tongue 31, tongue 31 of one unit and flap 28 of the cooperating unit are joined and held together. One

further feature of the structure of the box units should be pointed out and that is that, as most clearly shown in Fig. 1, one corner 33 of the inner top flap number 28 is cut away to provide stock for the projecting tongue 31. This feature is illustrated and described in greater detail in my said application, Serial Number 141,150. The fact that said corner is cut away at 33 is utilized in the assembly of the box units.

it will be understood that the bottom of each box unit X and Y likewise is formed with two inner flaps 128 and two outer flaps 129 and 130 and that outer flap 129 of each unit is provided with a projecting tongue 131, and outer flap 138 of each unit is provided with a corresponding recess 132 to receive the tongue 131 of the opposite box unit.

Although the machine which constitutes the subject of this invention may be used to close containers of other construction, said machine is most particularly adapted for closing the containers hereinbefore described.

The machine which comprises the subject matter of the invention is particularly designed for packing containers for small metal cans, such as baby food cans Z wherein twenty-four such cans are placed inside each unit X or Y and the combined pair of two container units contains forty-eight cans. it will be understood that the machine may readily be adapted for container units dimensional to receive cans or glass jars and the like of other dimensions and of different numbers.

The machine comprises a plurality of sections:

A. Packer station of standard construction, as well understood in the art to which this invention pertains. Twenty-four cans are simultaneously and automatically inserted in each unit X or Y.

Unit assembly station wherein each unit is centered laterally of the machine and the two units of each pair are brought together so that the opposed sides are abutting. At this station controls are provided so that single units will not proceed through the machine separately but that each pair will be grouped together and move through the machine together. This station comprises the subject matter of this invention.

C. Inner top flap closing station wherein the inner top fiaps are folded down so that they assume a horizontal position overlying the contents of the container.

D. Top and bottom outer flap unfolding station. The outer flaps are folded backward until they extend horizontally away from the containers.

E. Gluing station wherein glue is applied to the under surfaces of the outer flaps.

F. Outer flap refolding station wherein the outer top flaps and the outer bottom flaps are folded back so that they assume a horizontal position overlying the inner top and bottom flaps respectively.

G. First compression station wherein the pairs of units are moved by the conveyor bars through a compression unit which applies force to the top and bottom of the box so that the glue will adhere.

H. Second compression station wherein further compression is applied. The units are moved through the machine by conveyor belts in conventional manner.

Reference is made to said application Serial No. 188,254 for a complete description of the foregoing stations.

Unit assembly station At this station, shown in detail in Figs. 3 to 6, the pairs of box units X and Y are assembled together so that their side panels 24 abut and the tongues 31 and 131 of each unit overlap the opposite unit. It is very important that each pair of units be accurately assembled with said sides 24 abutting and the units square with respect to each other since this relationship insures proper sealing and interlocking of the units and prevents the units from breaking apart during subsequent transportation, a result which would otherwise occur.

Accordingly, there are provided on opposite sides of the machine, horizontally disposed side members 66. Said side members 66 are supported by standards 67, the height whereof being adjustable, as well understood in this art. Eleven horizontally disposed shafts 68 extending transversely across the machine are rotatably mounted in said side members 66, the axes of all said shafts being level. Each shaft 68 bears at each side of the machine a frusto-conical roller 69, fixed for rotation with its shaft 68, the smaller end of the roller being directed inwardly. Opposed rollers 69 are spaced apart a distance such that as the box units are discharged from the packer station conveyor belt 44, the opposite bottom side edges are supported by said frusto-conical rollers. in this mannor the outer bottom flaps 129 and 130 sag slightly downward so as to assume an acute angle with respect to the bottom inner flaps 127 and 128. This insures that the tongues 131 will overlap the opposite box unit; it also insures that the platen of the gluer will pass under the outer flaps 129 and 130 so as to permit folding backward of said outer flaps during passage through the gluer.

In order to insure proper passage of the units through the machine, as hereinafter appears, certain of shafts 68 are power driven and others are idlers. Thus the first two shafts are idlers 68(1) and 68(2); the next two shafts 68(3) and 68(4) are driven in unison; the next two shafts 68(5) and 68(6) are idlers; and the last five shafts 67(7) to 68(11) are power driven in unison. Shafts 68(3) and 68(4) each bears a sprocket 71 at one end which are driven by chain 72 which in turn passes over sprocket 73 on shaft 52. Shaft 68(7) bears an idler sprocket 74 at one end over which passes chain 72. The opposite end of shaft 68(7) and the corresponding ends of each of shafts 68(8), (9), and (10) bear sprockets '76 over which passes chain 77 driven by sprocket 76 on shaft 52, thus resulting in shafts 68(7)68(18) turning in unison. Shaft 68(11) bears a sprocket 75 driven by chain 72, thus resulting in shaft 68(11) being driven at a slower speed than shafts 67(7)68(ltt3).

Preferably shafts 68 are spaced apart a distance such that a single box unit X is of a length two and one-half times the distance between centers of shafts 68. This spacing plus the alternation of driven and idler shafts 63 facilitates proper passage of the units through the machine. By timing mechanism hereinafter described, the leading edge of each leading unit X is held immediately above the center of shaft 68( 11) until the trailing unit Y abuts unit X. Unit Y is pushed against unit X by a succeeding unit, which succeeding unit is urged forward by driven rollers 69 on shafts 68(3) and 68(4). Upon actuation of certain switches, later described, units X and Y are released and driven forward by driven rollers 69 on shafts 68(7)68(11). Any tendency of the succeeding unit to follow after unit Y is prevented by reason of the fact that shafts 68(5) and 63(6) are not driven and thus the succeeding unit comes to rest. A brake 78, which is likewise described in detail below, further assists in preventing the succeeding unit from following unit Y.

Similarly, as a unit comes off the conveyor belt 44, it is pushed forward by the suceeding unit until it is itself advanced by the rollers 69 on shafts 68(3) and 63(4). The result is that there is a gap between each unit except the abutting pair of units X and Y. The gaps between the other units permit entry of mechanism to stop the units and prevents ganging of the units through the machine.

As has been stated, timing devices are incorporated in this section of the machine so that units X and Y are collected as a pair and each pair moves through the machine together. Accordingly, stop members 81 are provided on opposite sides of the machine to hold the leading edges of the leading unit X. Four switches 82, 83, 34, and 85 are provided and an electrical circuit is established so that when each of said switches is closed, stop members 81 are retracted and the pair of units previously held thereby permitted to proceed through the machine. Limit switch 82 is provided adjacent stop members 81 and when the leading edge of the leading unit X comes to rest and is held by stop member 81, said switch 82 is closed. Limit switch 83 is provided so that when the leading edge of: the trailing unit Y of each pair comes to rest abutting the trailing edge of the leading unit, said switch is closed. The third switch 84 is actuated by cam 86 which rotates with conveyor bar sprocket shaft 87 and said switch 84 is so actuated that the conveyor which advances the units through the flap closing, gluing and compression stations-as described in detail in my said application Serial No. 188,254, will be in proper position to receive a pair of units when said switch is actuated. A fourth switch 85, normally closed, is provided in the path of the leading unit X beyond stops 89 (see Figs. 3 and 4). If, by accident, unit X is turned around so that tongue 131 projects forwardly, then switch 85 is opened and forward progress stopped until unit X is turned around by the operator.

The electrical circuit for actuation of the solenoids 109 which retract the stop members 81 is shown diagrammatically in Fig. 7. Upon closing of switches 82 and 83 by front and rear units X and Y, respectively, and upon closing of switch 84 by timing cam 86 on conveyor shaft 87, two-pole relay 111 is actuated to energize s'aid solenoids 109 and release the units X and Y simultaneously in precise timed relationship so that the conveyor will come up behind the trailing unit Y and push the two units X and Y through the gluer and compression units of the machine. It will further be seen from said wiring diagram Fig. 7, that if a tongue 131 contacts switch 85 (by reason of unit X being placed in the machine in the wrong direction), then the electric circuit which energizes the relay 111 is broken until the attendant places unit X in proper direction.

After solenoids 109 are actuated, passage of units X and Y breaks contact at switches 82 and 83 with the result that the circuit energizing said solenoids is broken. Rollers 93 roll along the side panels of units X and hence do not interfere with movement of said units X and Y. Immediately after passage of unit Y, stop member 81 is interposed to prevent passage of the succeeding unit.

Stop members 81, on opposite sides of the machine, are identical in construction. A horizontal bar 91 is provided which terminates at its inner end in a yoke shaped member 92, the arms of the yoke being vertically disposed with respect to each other. Rollers 93 are provided on each of the legs of the yoke 92 and said rollers are disposed to bear against the box unit X and hold it against movement except when said bar 91 is retracted, as hereinafter explained. Bar 91 is horizontally disposed within brackets 94 and 96 so that said bar may slide freely within the brackets in a horizontal direction transverse to the direction of movement of the unit through the machine. Bar 91 is biased inwardly by springs 97 which are helical in configuration and surround horizontal stub shafts 98. One end of each of the springs 97 bears against stationary vertical brackets 99 and the opposite end bears against a nut 101 which, in turn, bears against plate 102 to which bar 91 is connected. Thus, the force of springs 97 is transmitted to plate 102 and thence to bar 91 and urges said bar inwardly. Chain 103 is operatively connected to the bar 91 by means of threaded adjustment member 104 which is threaded into the end of bar 91 and thus by screwing the threaded adjustment member 104 into or out of the end of the bar 91 the effective length thereof may be adjusted. Chain 103 passes over idler sprocket 107 and thence is connected to the upper end of the armature 108 of solenoid 109, said solenoid being vertically disposed. Upon energization of said solenoid 109 upon closing of switches 82, 83, 84 and 85 chain 103 is pulled, which retracts bar 91 and thus permits a pair of 6 units to move past stop members 81 into the gluing portion of the machine.

In order to prevent a succeeding unit from following unit Y- through the machine upon release of the stop members 81, brake 78 is provided. Said brake 78 is located with respect to stop member 81 a distance rearwardly slightly greater than the length of two units and on one side of the machine. Thus if a succeeding unit should be in place immediately to the rear of unit Y, upon actuation of said brake said succeeding unit will be retarded so as not to follow unit Y into the gluer section.

' Brake 78, as shown particularly in Figs. 4-6 comprises a rubber-surfaced shoe 112 pivoted at its rearward end on a vertical axis to a stationary plate 113 mounted on the side member 66. A horizontally slidable pin 114 in said plate contacts and moves said shoe inwardly. Said pin 114 is actuated upon actuation on solenoid 109 as follows: Link 116 is directly connected at one end to yoke 92; the opposite end of said link 116 is pivotally connected to one end of rocker arm 117; rocker arm 117 is pivotally mounted intermediate its ends to stationary member 106; the end of rocker arm opposite link 116 bears pin 114. Therefore, retraction of stop member 81 results in inward movement of brake shoe 112 and thus holds up passage of additional units through the machine until stop member 81 is restored to position. Spring biases said shoe 112 outwardly except when brake 78 is actuated. On the side of the machine opposite brake 78 is brace 79 which restrains lateral displacement of a box unit engaged upon actuation of brake 78, the distance between brake 78 and brace 79 being about equal to the width of a box.

In order to insure proper alignment of the units through the Unit Assembly Station, at either side of the machine there are provided horizontal side guides 118 which are spaced apart a distance slightly greater than the width of units X and Y. Said guides 118 are elevated above the surface of rollers 69 a distance about equal to half the height of said units by vertical standards 119 fixed at their lower ends to side members 66. The elevation of said guides 118 is adjustable to accommodate units of difierent heights and the distance between said guides is also adjustable by reason of horizontal transverse connecting members 120 which are fixed at one end to guides 118 and adjustably held at their other end in brackets 121 carried by standard 119. Adjustment of elevation is accomplished by reason of the fact that brackets 121 are adjustable on standard 119.

it will be noted as a matter of terminology that in the claims switch 85 is referred to as the third switch, and switch 84 is referred to as the fourth switch.

Although the present invention has been described in some detail by way of illustration and example, it is understood that certain changes and modifications may be made within the spirit of the invention and scope of the appended claims.

What is claimed is:

l. Means for assembling groups of interlocking container units having projecting tongues overlapping adjacent units of the character described comprising a plurality of frusto-conical rollers positioned and arranged to engage the side bottom edges of said units to support the bottom outer flaps angularly disposed with respect to the bottom inner flaps to permit the tongue on one of said bottom outer ilaps to overlie the adjacent unit, stop means for arresting forward movement of said units, means for retracting said stop means, means for rotating a first group of rollers located at intervals rearwardly of said stop means over a total distance substantially equal to the length of a group of said units thereby urging said units forwardly, and a second group of idler rollers located rearwardly of the first group of rollers.

2. Means for assembling groups of interlocking container units having projecting tongues overlapping adjacent units of the character described comprising, first means engaging the side bottom edges of the said units and supporting said units with the bottom outer flaps angularly disposed with respect to the bottom inner flaps to permit the tongue on one of said bottom outer flaps to overlie the adjacent unit, second means biasing said units forward, stop means projectable for arresting forward movement of said group of units, a first switch located adjacent said stop means arranged to be closed upon a first unit abutting said stop means, a second switch located rearwardly of said first switch arranged to be closed upon a second unit abutting said first unit, and means for retracting said stop means operable only upon closing of said first and second switches.

3. Means for assembling groups of interlocking container units having projecting tongues overlapping adjacent units of the character described comprising, a plurality of frusto-conical rollers positioned and arranged to engage the side bottom edges of said units to support the bottom outer flaps angularly disposed with respect to the bottom inner flaps and to permit the tongue on one of said bottom outer flaps to overlie the adjacent unit, means for rotating some of said rollers for advancing said units, stop means projectable for arresting forward movement of said group of units, a first switch located adjacent said stop means arranged to be closed upon a first unit abutting said stop means, a second switch located rearwardly of said first switch arranged to be closed upon a second unit abutting said first unit, a third switch positioned and arranged to be opened upon contact by the projecting tongue of a unit positioned improperly in the machine, and means for retracting said stop means operable only upon said first, second and third switches being closed.

4. Means for assembling groups of interlocking container units of the character described having projecting tongues overlapping adjacent units comprising, a plurality of frusto-conical rollers positioned and arranged to engage the side bottom edges of said units to support the bottom outer flaps angularly disposed with respect to the bottom inner flaps and to permit the tongue on one of said bottom outer flaps to overlie the adjacent units, stop means for arresting forward movement of said units, means for retracting said stop means, and means for rotating a group of rollers located rearwardly of said stop means a distance substantially equal to the length of a group of said units thereby tending to advance said units, and a brake operable upon retracting of said stop means for restraining additional units from following said group of units beyond said stop means.

5. Means for assembling groups of interlocking container unit having projecting tongues overlapping adjacent units of the character described comprising, a plurality of frusto-conical rollers positioned and arranged to engage the side bottom edges of said units to support the bottom outer flaps angularly disposed with respect to the bottom inner flaps to permit the tongue on one of said bottom outer flaps to overlie the adjacent unit, means for rotating some of said rollers for advancing said units, stop means projectable for arresting forward movement of said group of units, a first switch located adjacent said stop means arranged to be closed upon a first unit abutting said stop means, a second switch located rearwardly of said first switch arranged to be closed upon a second unit abutting said first unit, a third switch positioned and arranged to be opened upon contact by the projecting tongue of a unit positioned improperly in the machine,

conveyor means located forwardly of said stop means, means for advancing said conveyor means, a fourth switch arranged to be closed in timed relation to movement of said conveyor means, means for retracting said step means upon closing of said four switches, and means for rotating a group of said rollers to advance said group of container units beyond said stop means, said fourth switch being timed to close upon said conveyor means reaching a position such that it will be moved into position behind said group of units to continue advancement of said group of units.

6. Means for assembling groups of interlocking container units having projecting tongues overlapping adjacent units of the character described comprising a plurality of frusto-conical rollers positioned and arranged to engage the side bottom edges of said units to support the bottom outer flaps angularly disposed with respect to the bottom inner flaps to permit the tongue on one of said bottom outer flaps to overlie the adjacent unit, means for rotating some of said rollers for advancing said units, stop means projectable for arresting forward movement of said group of units, a first switch located adjacent said stop means arranged to be closed upon a first unit abutting said stop means, a second switch located rearwardly of said first switch arranged to be closed upon a second unit abutting said first unit, a third switch positioned and arranged to be opened upon contact by the projecting tongue of a unit positioned improperly in the machine, conveyor means located forwardly of said stop means, means for advancing said conveyor means, a fourth switch arranged to be closed in timed relation to movement of said conveyor means, means for retracting said stop means upon closing of said four switches, and means for rotating a group of said rollers to advance said group of container units beyond said stop means, said fourth switch being timed to close upon said conveyor means reaching a position such that it will be moved into position behind said group of units to continue advancement of said group of units, and a brake operable upon retracting of said stop means for restraining additional units from following said group of units beyond said stop means.

7. Means for assembling pairs of container units in abutting relation comprising, guideways restraining lateral movement of said units, a retractable stop member having a projecting position restraining forward movement of said units and a retracted position, a first switch adjacent said stop member and arranged to be closed upon a first unit contacting said stop member, a second switch spaced rearwardly from said stop member and arranged to be closed upon a second unit abutting said first unit, and an electric circuit to move said stop member to retracted position, said circuit including said first and second switches in series.

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